• 대한치과교정학회지
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• 제20권2호
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• pp.217-226
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• 1990

The purposes of this study were to clarify the effect of tooth size and arch size upon the crowding. 175 upper casts were measured and following conclusions were made. 1. Tooth size, intermolar width, 2nd premolar width of crowded group were not significantly different from those of noncrowded groups. 2. Intercanine width, arch length of noncrowded group were significantly larger than crowded group. 3. Multiple regression equations were derived by using tooth size, arch perimeter, arch length, intermolar width.

• 대한치과교정학회지
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• 제24권4호
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• pp.773-785
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• 1994

It has been generally believed that the impaction or eruption of mandibular third molars has significant correlations with the growth of the mandible, size of mandibular arch and size of teeth. The purpose of this study was to examine if there is any correlation between the status of eruption of mandibular third molars and the amount of mandibular crowding. The effect of missing of third moalrs to mandibular crowding was studied as well. 140 adult students of Yonsei University were selected and divided into three groups according to the status of mandibular third molars, Group 1) congenital missing group, Group 2) eruption group, and Group 3) impaction group. The tooth size, dimensions of the mandibular dental arch, and the amount of crowding were measured and compared. Results were as follows ; 1. There was no statistically significant difference in tooth size between the missing group and the eruption group(p<0.05). Impaction group showed larger total tooth material, inci- sal tooth material, and individual tooth size except central incisors compared to missing group (p<0.05). Impaction group showed larger total tooth material, incisal tooth material compared to eruption group as well(p<0.05). When individual tooth size was compared, impaction group had larger central incisors, canines, and second premolars than eruption group(p<0.05). 2. Missing group showed larger intermolar width than impaction group and it was stati- stically significant(p<0.05). 3. When compared the amount of total crowding, impaction group showed the largest am- ount of crowding, then eruption group, and missing group showed the least amount of crowding respectively(p<0.05). There was no statistically significant difference between missing stoup and eruption group in the amount of incisal crowding(p<0.05). Impaction group show- ed the largest amount of incisal crowding among all three groups(p<0.05).

• 대한치과교정학회지
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• 제14권2호
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• pp.263-272
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• 1984

This study was undertaken to examine the extent to which tooth size and jaw size each contribute to dental crowding. Two groups of dental casts were selected on the basis of dental crowding. One group, consisting of 94 pairs of dental casts (46 males and 48 females) with normal occlusion. A second group, consisting of 84 pairs of dental casts (98 males and 46 females) with crowding. The results were as follows. 1. Means and standard deviations of the two groups were used to compare the two groups. 2. Significant differences were observed between two groups on the basis of tooth size, arch dimension and arch perimeter. 3. Between noncrowded group and crowded group, was crowded group was found to have large troth size than noncrowded group, while smaller arch dimension and perimeter. 4. Significant differences were observed between males and females on the basis of tooth size, arch dimension and arch perimeter. 5. Author found ideal arch shape of normal occlusion.

• 대한치과교정학회지
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• 제29권4호
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• pp.491-501
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• 1999

본 연구는 석고모형 분석 중 치아크기 측정시 발생할 수 있는 오차를 줄이고 측정의 재현도와 정확성을 향상시키는데 도움이 될 수 있는 방안을 모색하고자 시행되었다. 치아밀집 치열 특징을 지닌 상하악 20조의 석고모형을 대상으로 하여, 5명의 조사자가 각 치아의 근원심 폭경을 디지털 버니어 캘리퍼스를 사용하여 2주 간격으로 3회 측정하여 실험측정치를 얻은 다음, 측정에 이용된 석고모형을 근원심 접촉점 부위에서 개개 치아로 분리한 후, 마이크로미터를 이용하여 측정한 표준치와 비교$\cdot$분석하여 다음과 같은 결과를 얻었다. 1. 3회 측정에 따른 재현도는 조사자별 치아별로 큰 차이를 나타내지 않았다. 2. 표준치와 비교한 계측오차는 조사자별 또는 치아별로 차이를 보였다. 3. 표준치와의 오차는 전치에서 구치로 갈수록 증가하여 제1대구치에서 가장 큰 차이를 나타내었다. 4. 표준치와 비교시 전반적으로 작게 측정하는 경향을 보였으며 이에 대한 치아별, 조사자별 차이가 두드러졌다. 5. 전반적인 오차 발생 정도는 치아밀집 정도와 유의한 상관성을 보이지 않았다. 이상의 결과는 교정증례 분석시 치아크기 계측오차 발생 가능성의 고려가 필요함을 시사하였다.

• 대한치과의사협회지
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• 제41권7호통권410호
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• pp.504-508
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• 2003

This report demonstrates a case of tooth autotransplantation into the oroantral fistula site after extraction. Oroantral fistula can be developed when maxillary molar or premolar is extracted in case the root of tooth closed to or inside maxillary sinus. In most of cases, this would heal spontaneously without any interventions. Sometimes, many procedures including flap closure would be used judging from perforating size and previous inflammation. Although fistula size of this case is not that large, closure with tooth autotransplanted has successfully accomplished. So this report will discuss about several clinical aspects.

• 대한치과교정학회지
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• 제33권3호
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• pp.157-167
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• 2003

본 연구는 치아크기와 악골크기의 상관관계를 살펴보고자 교정치료경험이 없고 교합이 양호한 87명 (남자49명, 여자38명)의 치아경석고모형과 두부방사선사진을 평가하였다. 치아크기는 치아의 근원심 최대폭경을 디지털 버니어 캘리퍼스를 이용하여 반복 측정하였고 악골의 크기는 기존의 여러 두부방사선계측법에서 이용된 악골의 선계측치를 반복 측정하였다. 치아와 악골크기 모두 성별에 따라 다르게 측정하였다. 치아크기와 악골크기 사이의 상관관계를 알아보기 위해 피어슨 상관관계분석을 실시하였다. 결과는 다음과 같다. 1.성별에 따라 두 군으로 나뒀을 경우 악골크기와 치아크기가 두 군에서 유의성 있게 다르게 나타났다. 2.남자군에서는 상악골과 상악치아 크기는 유의한 상관관계를 보이지만 여자군에서는 상악골과 상악치아 크기는 거의 상관관계를 보이지 않았다. 3. 남자군에서는 상악골의 크기를 나타내는 PTM vert-ANS vert (FH plane)과 PTM vert-A vert (palatal plane)는 모든 상악치아와 유의성 있는 상관관계를 보였으며 상악중절치는 상악골에 관계된 모든 계측치들과 유의성 있는 상관관계를 보였다. 4. 남여 모두에서 하악골의 크기를 나타내는 B vert- Point J vert (mandibular plane)는 하악치아와 유의성 있는 상관관계를 보였다. 위의 결과에서 자연적으로 나타나는 정상교합에서 치아와 악골크기는 상관관계가 낮거나 거의 없음을 알 수 있다.

• 수산해양기술연구
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• 제50권4호
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• pp.530-541
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• 2014

The dredge gear is dragged along the bottom of the sea to catch targeted edible bottom dwelling species. Species composition and ecological index of the catches of dredge were estimated around Gangneung coastal fishing ground by dredge with different mesh size and tooth space from July to December 2013. Eight different types of dredge including four different tooth space (24.7 mm, 29.9 mm, 34.9 mm, 40.1 mm) and four different mesh size(15.5 mm, 32.7 mm, 51.1 mm, 60.0 mm) were used in the experiment. During the experiment, total catches were collected 31 species as sipunculida 1 species, mollusca 13 species, annelida 3 species, arthropoda 8 species, echinodermata 4 species and others 2 species. The dominant genus were mollusca and echinodermata while the dominant species were Megangulus venulosus, Pseudocardium sachalinensis, Schaphechinus brevis. The richness index was ranged 1.29-1.72, evenness index was 0.6-0.65 and diversity index was 1.65-1.83 according to the tooth space and mesh size of dredge. Richness index, diversity index were high at tooth space 34.9 mm dredge and ecological index showed decreasing tendency with the increasing of mesh size of dredge. Cluster and MDS analysis, based on a Bray-Curtis and similarity matrix of fourth root transformed data of number of species and wet weight, showed division into four different groups as four different tooth space (Group A), four different mesh size Group B (51.1 mm, 60.0 mm), Group C (32.7 mm) and Group D (15.5 mm).

• 대한치과의사협회지
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• 제15권2호
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• pp.107-110
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• 1977

Class I malocclusion is essentially a dental dysplasia. Rotations, individual tooth malpositions, missing teeth, tooth size discrepancies, etc., fall under this classification. There are two types of class I malocclusions. One is identified by and insufficient denture base to accommodate the teeth; the other has more denture base than tooth material, creating spaces in the arch. The tooth material-to denture base discrepancies may be slight, calling for only a little increase in arch length for alignment and the correction of minor rotations. Discrepancies may also be great, in which case it becomes necessary to reduce tooth material by extraction, so as to make the tooth material more in proportion to the size of the denture base. The author had attempted orthodontic treatment of a class I malocclusion case of 13-year old boy in which high canines and impacted mandibular second premolars were involved. The author obtained good results.

• 대한치과의사협회지
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• 제48권3호
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• pp.196-204
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• 2010

To establish the ideal occlusal relationship, the values of tooth size and ratio must be in a normal range. In this study, the means and standard deviations of Bolton's anterior ratio and overall ratio using mesiodistal dimensions of teeth measured on diagnostic models of 334 Korean malocclusion patients were calculated and differences in Bolton ratio according to the groups of malocclusion patients were studied. Also the changes that can occur in overall ratio before and after hypothetical tooth extractions were observed. The results are as follows. 1. The mean anterior ratio of Korean malocclusion patients was $78.0\;{\pm}\;2.69%$, and the mean overall ratio was $91.56\;{\pm}\;2.28%$. 2. The largest value of tooth size ratio could be found in Class III group, followed by Class I and Class II groups in order. However there was no statically significant difference. 3. The values of overall ratio reduced significantly after premolar extractions in all malocclusion groups, which was much more significant in the extraction of upper second premolar and lower first premolar(U5L4) or upper second premolar and lower second premolar(U5L5). 4. The values of overall ratio reduced significantly after premolar extractions in all 3 groups divided based on Bolton ratio, which was much more significant in the extraction of upper second premolar and lower first premolar(U5L4) or upper second premolar and lower second premolar(U5L5).

• The Journal of Advanced Prosthodontics
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• 제8권3호
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• pp.241-250
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• 2016

Oligodontia is defined as a congenital tooth agenesis with the absence of six or more permanent teeth. This clinical report describes a patient with non-syndromic partial oligodontia, with retained deciduous teeth and the absence of 16 permanent teeth. Anterior esthetic problems were caused by interarch tooth size discrepancy, interdental space, aberrant tooth dimensions, and the absence of centric contacts of the anterior teeth. Prosthetic restoration after orthodontic and implant treatment was performed with a multi-disciplinary team approach. Favorable functional and esthetic results were obtained using a definitive prosthesis.